Semiconductor device, method for manufacturing the same, and electronic device

ABSTRACT

Disclosed herein is a semiconductor device including: a first semiconductor chip having an electronic circuit section and a first connecting section formed on one surface thereof; a second semiconductor chip having a second connecting section formed on one surface thereof, the second semiconductor chip being mounted on the first semiconductor chip with the first and the second connecting sections connected to each other by a bump; a dam formed to fill a gap between the first and the second semiconductor chips on a part of an outer edge of the second semiconductor chip, the part of the outer edge being on a side of a region of formation of the electronic circuit section; and an underfill resin layer filled into the gap, protrusion of the resin layer from the outer edge of the second semiconductor chip to a side of the electronic circuit section being prevented by the dam.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a semiconductor device, a method formanufacturing the same, and an electronic device, and particularly to asemiconductor device packaged by mounting a second semiconductor chip ona first semiconductor chip having an electronic circuit section such asa solid-state imaging element section or the like, a method formanufacturing the same, and an electronic device having the same.

2. Description of the Related Art

A package structure referred to as a chip-on-chip (CoC) package, whichincludes a plurality of semiconductor chips laminated and sealed withinthe single package to achieve miniaturization, high functionality andthe like of a semiconductor device, has been put to practical use.

The CoC package is also applied to for example a structure in which amemory element and a processor element are laminated, and progress hasbeen made in practical use of the CoC package as a SIP (System inPackage) type semiconductor device.

For example, when an SIP is formed by a CoC package as in JapanesePatent Laid-Open No. 2008-192815 (hereinafter referred to as PatentDocument 1), the application of flip chip connection is principallyconsidered for connection between an upper semiconductor chip and alower semiconductor chip.

In the case where flip chip connection is applied to connection betweensemiconductor chips in a CoC package, a first semiconductor chip (lowerstage side semiconductor chip) is mounted on a wiring board having anexternal connection terminal and the like.

A second semiconductor chip (upper stage side semiconductor chip) isflip-chip-connected to the first semiconductor chip.

That is, electrical and mechanical connection between the first andsecond semiconductor chips is made by connecting a bump electrodeprovided on the upper surface of the first semiconductor chip and a bumpelectrode provided on the lower surface of the second semiconductor chipto each other.

Further, an underfill resin layer is filled into a gap between the firstand second semiconductor chips to improve connection reliability and thelike.

Japanese Patent Laid-Open Nos. 2005-276879, 2008-252027 and 2008-124140(hereinafter referred to as Patent Document 2, 3 and 4, respectively),for example, disclose techniques for forming a dam that serves to stopthe flow of the underfill resin layer in the case of the structure inwhich the gap between the first and second semiconductor chips of theCoC package is filled with the underfill resin layer.

The dam is intended mainly to prevent resin contamination caused by aflow of the underfill resin layer into an electronic circuit sectionsuch as an Al electrode formed in the first semiconductor chip in aperipheral part of a mounting region of the second semiconductor chip.

In the CoC package of the above-described constitution, a reactant gasis emitted from a fillet of the underfill resin layer, which fillet isformed at the peripheral part of the second semiconductor chip, at atime of resin curing reaction.

In Patent Documents 1 to 4, when a distance between the electroniccircuit section such as the Al electrode and the like and the uppersemiconductor chip is shortened to miniaturize the CoC package, theabove-described gas contaminates the electronic circuit section such asthe Al electrode and the like.

As a result, a failure in wire bonding and a degradation in reliabilityoccur, and it is therefore difficult to miniaturize the CoC package.

In addition, in a case where a solid-state imaging element section isformed on the lower semiconductor chip, even when a dam is formedbetween the solid-state imaging element section and the uppersemiconductor chip, the imaging element section is contaminated by thereactant gas emitted from the fillet of the above-described underfillresin layer, and thus an imaging characteristic is degraded.

In addition, a semiconductor device in which rewiring is formed on aglass substrate or the like and a semiconductor chip having asolid-state imaging section formed thereon is flip-chip-connected isunder study.

In order to prevent a resin protecting a bump electrode fromcontaminating the light receiving surface of the solid-state imagingsection, techniques for forming a dam between the bump electrode and thesemiconductor chip having the solid-state imaging section formed thereonare under study.

However, reference to Japanese Patent Laid-Open Nos. 2007-533131,2002-118207 and Hei 06-204442 (hereinafter referred Patent Document 5, 6and 7, respectively) and the like shows that a dam made of a resin isformed on only the side of the glass substrate, and that there is aproblem in a sealing property for the side of the semiconductor chiphaving the solid-state imaging section formed thereon.

In addition, this technique can essentially form a bump electrode onlyin a peripheral part of a laminated semiconductor chip or thesemiconductor chip having a solid-state imaging section formed thereon.

Further, in semiconductor devices disclosed in Patent Documents 6 and 7,no dam is formed on the side of an Al electrode, and there is thus afear of contamination of the Al electrode.

SUMMARY OF THE INVENTION

A problem to be solved is that when the distance between the electroniccircuit section formed on the lower semiconductor chip and the uppersemiconductor chip is shortened, the electronic circuit section iscontaminated by the reactant gas emitted from the fillet of theunderfill resin layer between the upper semiconductor chip and the lowersemiconductor chip.

It is thus difficult to achieve miniaturization and a higher degree ofintegration of the semiconductor device by shortening the distancebetween the upper semiconductor chip and the electronic circuit sectionformed on the lower semiconductor chip.

According to an embodiment of the present invention, there is provided asemiconductor device including: a first semiconductor chip having anelectronic circuit section formed at least on one surface of the firstsemiconductor chip, and having a first connecting section formed on asame surface as the surface of formation of the electronic circuitsection; a second semiconductor chip having a second connecting sectionformed on one surface of the second semiconductor chip, the secondsemiconductor chip being mounted on the first semiconductor chip withthe first connecting section and the second connecting section connectedto each other by a bump; a dam formed so as to fill a gap between thefirst semiconductor chip and the second semiconductor chip on at least apart of an outer edge of the second semiconductor chip, the part of theouter edge of the second semiconductor chip being on a side of a regionof formation of the electronic circuit section; and an underfill resinlayer filled into the gap between the first semiconductor chip and thesecond semiconductor chip, protrusion of the underfill resin layer fromthe outer edge of the second semiconductor chip to a side of theelectronic circuit section being prevented by the dam.

In the semiconductor device according to the above-described embodimentof the present invention, a second semiconductor chip having a secondconnecting section formed on one surface of the second semiconductorchip is mounted on a first semiconductor chip having an electroniccircuit section formed at least on one surface of the firstsemiconductor chip, and having a first connecting section formed on asame surface as the surface of formation of the electronic circuitsection, with the first semiconductor chip and the second semiconductorchip connected to each other at the first connecting section and thesecond connecting section by a bump.

In this case, a dam for filling a gap between the first semiconductorchip and the second semiconductor chip is formed on at least a part ofan outer edge of the second semiconductor chip, the part of the outeredge of the second semiconductor chip being on a side of a region offormation of the electronic circuit section.

An underfill resin layer is filled into the gap between the firstsemiconductor chip and the second semiconductor chip, protrusion of theunderfill resin layer from the outer edge of the second semiconductorchip to a side of the electronic circuit section being prevented by thedam.

In addition, according to an embodiment of the present invention, thereis provided a method for manufacturing a semiconductor device, themethod including the steps of: forming an electronic circuit section atleast on one surface of a first semiconductor chip, and forming a firstconnecting section on a same surface as the surface of formation of theelectronic circuit section; forming a second connecting section on onesurface of a second semiconductor chip; mounting the secondsemiconductor chip on the first semiconductor chip with the firstconnecting section and the second connecting section connected to eachother by a bump; forming a dam for filling a gap between the firstsemiconductor chip and the second semiconductor chip on at least a partof an outer edge of the second semiconductor chip, the part of the outeredge of the second semiconductor chip being on a side of a region offormation of the electronic circuit section; and forming an underfillresin layer so as to fill the underfill resin layer into the gap betweenthe first semiconductor chip and the second semiconductor chip,protrusion of the underfill resin layer from the outer edge of thesecond semiconductor chip to a side of the electronic circuit sectionbeing prevented by the dam.

In the method for manufacturing the semiconductor device according tothe above-described embodiment of the present invention, an electroniccircuit section is formed at least on one surface of a firstsemiconductor chip, and a first connecting section is formed on a samesurface as the surface of formation of the electronic circuit section.

In addition, a second connecting section is formed on one surface of asecond semiconductor chip.

Next, the second semiconductor chip is mounted on the firstsemiconductor chip with the first connecting section and the secondconnecting section connected to each other by a bump.

In the above, a dam for filling a gap between the first semiconductorchip and the second semiconductor chip is formed on at least a part ofan outer edge of the second semiconductor chip, the part of the outeredge of the second semiconductor chip being on a side of a region offormation of the electronic circuit section.

Next, an underfill resin layer is formed so as to be filled into the gapbetween the first semiconductor chip and the second semiconductor chip,protrusion of the underfill resin layer from the outer edge of thesecond semiconductor chip to a side of the electronic circuit sectionbeing prevented by the dam.

According to an embodiment of the present invention, there is providedan electronic device including: a solid-state imaging device; an opticalsystem for guiding incident light to an imaging section of thesolid-state imaging device; and a signal processing circuit forprocessing an output signal of the solid-state imaging device; whereinthe solid-state imaging device includes a first semiconductor chiphaving a solid-state imaging section formed at least on one surface ofthe first semiconductor chip, and having a first connecting sectionformed on a same surface as the surface of formation of the solid-stateimaging section, a second semiconductor chip having a second connectingsection formed on one surface of the second semiconductor chip, thesecond semiconductor chip being mounted on the first semiconductor chipwith the first connecting section and the second connecting sectionconnected to each other by a bump, a dam formed so as to fill a gapbetween the first semiconductor chip and the second semiconductor chipon at least a part of an outer edge of the second semiconductor chip,the part of the outer edge of the second semiconductor chip being on aside of a region of formation of the solid-state imaging section, and anunderfill resin layer filled into the gap between the firstsemiconductor chip and the second semiconductor chip, protrusion of theunderfill resin layer from the outer edge of the second semiconductorchip to a side of the solid-state imaging section being prevented by thedam.

The electronic device according to the above-described embodiment of thepresent invention includes: a solid-state imaging device; an opticalsystem for guiding incident light to an imaging section of thesolid-state imaging device; and a signal processing circuit forprocessing an output signal of the solid-state imaging device.

In the solid-state imaging device, a second semiconductor chip having asecond connecting section formed on one surface of the secondsemiconductor chip is mounted on a first semiconductor chip having asolid-state imaging section formed at least on one surface of the firstsemiconductor chip, and having a first connecting section formed on asame surface as the surface of formation of the solid-state imagingsection, with the first semiconductor chip and the second semiconductorchip connected to each other at the first connecting section and thesecond connecting section by a bump. In addition, a dam for filling agap between the first semiconductor chip and the second semiconductorchip is formed on at least a part of an outer edge of the secondsemiconductor chip, the part of the outer edge of the secondsemiconductor chip being on a side of a region of formation of thesolid-state imaging section. Further, an underfill resin layer is filledinto the gap between the first semiconductor chip and the secondsemiconductor chip, protrusion of the underfill resin layer from theouter edge of the second semiconductor chip to a side of the solid-stateimaging section being prevented by the dam.

In the semiconductor device according to the above-described embodimentof the present invention, the dam prevents the protrusion of theunderfill resin layer between the first and second semiconductor chipsfrom the outer edge of the second semiconductor chip to the side of theelectronic circuit section. Thus, the fillet of the underfill resinlayer is not formed in the vicinity of the electronic circuit section,and the contamination of the electronic circuit section by a reactantgas emitted from the fillet is prevented.

Thus, it is possible to shorten the distance between the electroniccircuit section formed on the first semiconductor chip and the secondsemiconductor chip, and thus achieve miniaturization and a higher degreeof integration of the semiconductor device.

The method for manufacturing the semiconductor device according to theabove-described embodiment of the present invention forms the dam toprevent the protrusion of the underfill resin layer between the firstand second semiconductor chips from the outer edge of the secondsemiconductor chip to the side of the electronic circuit section. Thus,the fillet of the underfill resin layer is not formed in the vicinity ofthe electronic circuit section, and the contamination of the electroniccircuit section by a reactant gas emitted from the fillet can beprevented.

Thus, it is possible to shorten the distance between the electroniccircuit section formed on the first semiconductor chip and the secondsemiconductor chip, and thus achieve miniaturization and a higher degreeof integration of the semiconductor device.

In the solid-state imaging device forming the electronic deviceaccording to the above-described embodiment of the present invention,the dam prevents the protrusion of the underfill resin layer between thefirst and second semiconductor chips from the outer edge of the secondsemiconductor chip to the side of the solid-state imaging section. Thus,the fillet of the underfill resin layer is not formed in the vicinity ofthe solid-state imaging section, and the contamination of thesolid-state imaging section by a reactant gas emitted from the fillet isprevented.

Thus, it is possible to shorten the distance between the solid-stateimaging section formed on the first semiconductor chip and the secondsemiconductor chip, and thus achieve miniaturization and a higher degreeof integration of the solid-state imaging device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a plan view of a semiconductor device according to a firstembodiment of the present invention, and FIG. 1B and FIG. 1C areschematic sectional views taken along lines X-X′ and Y-Y′, respectively,of FIG. 1A;

FIG. 2A is a plan view of a first semiconductor chip according to thefirst embodiment of the present invention, and FIG. 2B and FIG. 2C areschematic sectional views taken along lines X-X′ and Y-Y′, respectively,of FIG. 2A;

FIG. 3A is a plan view of a second semiconductor chip according to thefirst embodiment of the present invention, and FIG. 3B and FIG. 3C areschematic sectional views taken along lines X-X′ and Y-Y′, respectively,of FIG. 3A;

FIG. 4A is a plan view showing a process of manufacturing thesemiconductor device according to the first embodiment of the presentinvention, and FIG. 4B and FIG. 4C are schematic sectional views takenalong lines X-X′ and Y-Y′, respectively, of FIG. 4A;

FIG. 5A is a plan view showing a process of manufacturing thesemiconductor device according to the first embodiment of the presentinvention, and FIG. 5B and FIG. 5C are schematic sectional views takenalong lines X-X′ and Y-Y′, respectively, of FIG. 5A;

FIG. 6A is a plan view showing a process of manufacturing thesemiconductor device according to the first embodiment of the presentinvention, and FIG. 6B and FIG. 6C are schematic sectional views takenalong lines X-X′ and Y-Y′, respectively, of FIG. 6A;

FIG. 7A is a plan view of a semiconductor device according to a secondembodiment of the present invention, and FIG. 7B and FIG. 7C areschematic sectional views taken along lines X-X′ and Y-Y′, respectively,of FIG. 7A;

FIG. 8A is a plan view of a semiconductor device according to a thirdembodiment of the present invention, and FIG. 8B and FIG. 8C areschematic sectional views taken along lines X-X′ and Y-Y′, respectively,of FIG. 8A;

FIG. 9A and FIG. 9B are sectional views showing a process ofmanufacturing a semiconductor device according to a fourth embodiment ofthe present invention, and are schematic sectional views correspondingto the lines X-X′ and Y-Y′ in the semiconductor device shown in FIGS. 1Ato 1C;

FIG. 10A is a plan view of a semiconductor device according to a fifthembodiment of the present invention, and FIG. 10B and FIG. 10C areschematic sectional views taken along lines X-X′ and Y-Y′, respectively,of FIG. 10A;

FIG. 11A and FIG. 11B are sectional views showing a process ofmanufacturing the semiconductor device according to the fifth embodimentof the present invention, and are schematic sectional viewscorresponding to the lines X-X′ and Y-Y′ in the semiconductor deviceshown in FIGS. 10A to 10C; and

FIG. 12 is a schematic block diagram of an electronic device accordingto a sixth embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of a solid-state imaging device, a method formanufacturing the same, a designing method, and an electronic deviceaccording to the present invention will hereinafter be described withreference to the drawings.

Incidentally, description will be made in the following order.

1. First Embodiment (Basic Constitution of Semiconductor Device andManufacturing Method)

2. Second Embodiment (Constitution in which Electronic Circuit Sectionand Second Semiconductor Chip are Formed so as to be Adjacent to EachOther)

3. Third Embodiment (Constitution in which Dam is Formed in Shape alongOuter Edge of Second Semiconductor Chip)

4. Fourth Embodiment (Manufacturing Method Using Resin Film as UnderfillResin Layer)

5. Fifth Embodiment (Constitution in which Dam is Formed by Resin)

6. Sixth Embodiment (Application to Electronic Device)<

First Embodiment Constitution of Semiconductor Device

FIG. 1A is a plan view of a semiconductor device according to a presentembodiment. FIG. 1B and FIG. 1C are schematic sectional views takenalong lines X-X′ and Y-Y′, respectively, of FIG. 1A.

An electronic circuit section is formed at least on one surface of afirst semiconductor chip 10.

A solid-state imaging section 11, for example, is formed as theelectronic circuit section described above.

In the solid-state imaging section 11, for example, photodiodes areformed so as to be divided from each other for each pixel, and pixelsincluding photodiodes are arranged in the form of a matrix to form alight receiving surface. For example, an insulating film, a colorfilter, an on-chip lens and the like are formed on the light receivingsurface as required.

In addition, a pad electrode 12, for example, is formed as theelectronic circuit section.

The pad electrode 12 is formed of aluminum, for example. The padelectrode 12 is buried in the vicinity of a top layer of the firstsemiconductor chip 10. A part of the pad electrode 12 is exposed on thetop surface side by a pad opening part 12 a.

In addition, other peripheral circuit sections such for example as acomparator and a DA converter may be included as the electronic circuitsection.

For example, internal wiring 13 connected to the solid-state imagingsection 11, the pad electrode 12 and the like is formed so as to beburied within the first semiconductor chip 10.

An under bump film 20 as a first connecting section is formed on thesame surface of the first semiconductor chip 10 as the surface of thefirst semiconductor chip 10 on which surface the electronic circuitsection is formed.

On the other hand, wiring 31 and the like are formed on a secondsemiconductor chip 30, and an under bump film 32 as a second connectingsection is formed on one surface of the second semiconductor chip 30.

The second semiconductor chip 30 is mounted on the first semiconductorchip 10, the first semiconductor chip 10 and the second semiconductorchip 30 being connected to each other at the under bump film 20 and theunder bump film 32 by bumps 24.

In this case, a dam 25 for filling a gap between the first semiconductorchip 10 and the second semiconductor chip 30 is formed on at least apart of an outer edge of the second semiconductor chip 30 which part ison the side of a region in which the electronic circuit section isformed.

In addition, in the present embodiment, an under bump film 22 is formedon the side of the first semiconductor chip 10, and an under bump film34 is formed on the side of the second semiconductor chip 30. Theabove-described dam 25 is formed so as to connect the under bump film 22and the under bump film 34 to each other. The dam 25 is formed by thesame layer as a conductive layer forming the bumps 24. Bumps 23 areformed on the first semiconductor chip 10 in regions other than a regionformed such that the gap between the first semiconductor chip 10 and thesecond semiconductor chip 30 is filled. The dam 25 and the bumps 23together form a ring shape.

The gap between the first semiconductor chip 10 and the secondsemiconductor chip 30 is filled with an underfill resin layer 26, theprotrusion of the underfill resin layer 26 from the outer edge of thesecond semiconductor chip 30 to the side of the electronic circuitsection being prevented by the dam 25.

In the semiconductor device according to the present embodiment, theunderfill resin layer 26 has a fillet 26 a at a peripheral part of thesecond semiconductor chip 30 on which peripheral part the dam 25 is notformed.

However, the above-described dam 25 prevents the protrusion of theunderfill resin layer 26 from the outer edge of the second semiconductorchip 30 to the side of the electronic circuit section.

For example, in order to prevent contamination from a reactant gas fromthe fillet, it is important to secure a distance of 200 μm or morebetween the fillet and the electronic circuit section.

In the present embodiment, a distance of 200 μm or more can be securedbetween the fillet of the underfill resin layer 26 and the electroniccircuit section such as the solid-state imaging device, the padelectrode and the like.

Therefore, the contamination of the electronic circuit section by areactant gas emitted at a time of resin curing reaction from the filletof the underfill resin layer 26 can be prevented.

In the above-described embodiment, a constitution having the solid-stateimaging device and the pad electrode as the electronic circuit sectionhas been shown. However, the embodiment is applicable to a case whereone of the solid-state imaging device and the pad electrode or anelectronic circuit section whose contamination by another reactant gasis desirably avoided is present.

As described above, in the present embodiment, when the electroniccircuit section is provided in each of parts adjacent to two opposedsides of the second semiconductor chip, a dam is formed on the twosides. When the electronic circuit section is provided on another sideor a plurality of sides, it suffices to form a dam on the side or theplurality of sides.

A material for forming the dam 25 may be formed by a same layer as thebumps formed on the first or second semiconductor chip, or may be adifferent layer. For example, a metal such as Cu, An, Ti or the like ora soldering material such as Sn, SnAg, SnAgCu, SnCu, AuSn or the likecan be used.

Thus, the second semiconductor chip and the electronic circuit sectionsuch as the pad electrode, the solid-state imaging device or the likecan be brought into proximity to each other, and thus the semiconductordevice can be miniaturized.

[Method for Manufacturing Semiconductor Device]

A method for manufacturing the semiconductor device according to thepresent embodiment will next be described with reference to FIGS. 2A to6C.

FIG. 2A is a plan view of the first semiconductor chip according to thepresent embodiment. FIG. 2B and FIG. 2C are schematic sectional viewstaken along lines X-X′ and Y-Y′, respectively, of FIG. 2A.

An electronic circuit section is formed at least on one surface of thefirst semiconductor chip 10. A solid-state imaging section 11, forexample, is formed as the above-described electronic circuit section.

In the solid-state imaging section 11, for example, photodiodes areformed so as to be divided from each other for each pixel, and pixelsincluding photodiodes are arranged in the form of a matrix to form alight receiving surface. For example, an insulating film, a colorfilter, an on-chip lens and the like are formed on the light receivingsurface as required.

In addition, a pad electrode 12, for example, is formed as theelectronic circuit section.

The pad electrode 12 is formed of aluminum, for example. The padelectrode 12 is formed so as to be buried in the vicinity of a top layerof the first semiconductor chip 10. A pad opening part 12 a is formed soas to expose a part of the pad electrode 12.

In addition, other peripheral circuit sections such for example as acomparator and a DA converter may be included as the electronic circuitsection.

In addition, for example, internal wiring 13 connected to thesolid-state imaging section 11, the pad electrode 12 and the like isformed so as to be buried within the first semiconductor chip 10.

An under bump film 20 as a first connecting section is formed on thesame surface of the first semiconductor chip 10 as the surface of thefirst semiconductor chip 10 on which surface the electronic circuitsection is formed.

In addition, an under bump film 22 of a ring shape is formed on aperipheral part of a region for mounting a second semiconductor chipincluding a region for forming a dam.

Bumps 21 and 23 made of solder or the like are respectively formed onthe under bump film 20 and the under bump film 22 described above.

The bump 23 is formed in a ring shape on the peripheral part of theregion for mounting the second semiconductor chip as described above.

FIG. 3A is a plan view of the second semiconductor chip according to thepresent embodiment. FIG. 3B and FIG. 3C are schematic sectional viewstaken along lines X-X′ and Y-Y′, respectively, of FIG. 3A.

Wiring 31 and the like are formed on the second semiconductor chip 30,and an under bump film 32 as a second connecting section is formed onone surface of the second semiconductor chip 30.

In addition, an under bump film 34 of a linear shape is formed on twosides of an outer edge of the second semiconductor chip, the two sidesbeing a region for forming the dam.

Bumps 33 and 35 made of solder or the like are respectively formed onthe under bump film 32 and the under bump film 34 described above.

The bumps 35 are formed in a linear shape on the two sides of the outeredge of the second semiconductor chip as described above.

FIG. 4A is a plan view showing a process of manufacturing thesemiconductor device according to the present embodiment. FIG. 4B andFIG. 4C are schematic sectional views taken along lines X-X′ and Y-Y′,respectively, of FIG. 4A.

Using a collet 40 or the like as appropriate, the bumps 21 and the bump23 of the first semiconductor chip 10 described above are aligned withthe bumps 33 and the bumps 35 of the second semiconductor chip 30, andthe second semiconductor chip 30 is mounted on the first semiconductorchip 10.

FIG. 5A is a plan view showing a process of manufacturing thesemiconductor device according to the present embodiment. FIG. 5B andFIG. 5C are schematic sectional views taken along lines X-X′ and Y-Y′,respectively, of FIG. 5A.

Using a bonding head 41 or the like as appropriate, a breaking point isproduced in a surface oxide film by press contact below a solder meltingpoint, and after heating to a solder melting temperature, the soldersare connected to each other by oscillation operation in an X-directionand a Y-direction, so that the bumps 21 and the bumps 33 are integratedinto bumps 24.

At the same time as the above, the bump 23 and the bumps 35 areintegrated into a dam 25 in the region for forming the dam.

As described above, in the present embodiment, when the electroniccircuit section is provided in each of parts adjacent to two opposedsides of the second semiconductor chip, a dam is formed on the twosides. When the electronic circuit section is provided on another sideor a plurality of sides, a dam is formed on the side or the plurality ofsides.

In addition, no problem is presented even when a flux is applied inadvance in connecting the bumps made of solder. Incidentally, the bump23 and the bumps 35 to form the dam may each be formed at the same timeas or separately from the bumps 21 of the first semiconductor chip 10and the bumps 33 of the second semiconductor chip 30.

FIG. 6A is a plan view showing a process of manufacturing thesemiconductor device according to the present embodiment. FIG. 6B andFIG. 6C are schematic sectional views taken along lines X-X′ and Y-Y′,respectively, of FIG. 6A.

An underfill resin layer 26 is formed so as to be filled into the gapbetween the first semiconductor chip 10 and the second semiconductorchip 30, the protrusion of the underfill resin layer 26 from the outeredge of the second semiconductor chip 30 to the side of the electroniccircuit section such as the solid-state imaging section 11, the padelectrode 12 and the like being prevented by the dam 25.

Using a dispenser 26 d, for example, a resin in a liquid form whichresin is to form the underfill resin layer is injected into the gapbetween the first semiconductor chip 10 and the second semiconductorchip 30.

In filling the above-described resin, a resin injection port and an airoutlet port, for example, are desirably formed to secure a passage foran air to escape from the gap between the first semiconductor chip 10and the second semiconductor chip 30.

As described above, in the present embodiment, the electronic circuitsection is provided in each of parts adjacent to two opposed sides ofthe second semiconductor chip. One of sides other than the above sidesis an injection port for the resin, and the other side is an air outletport.

A thermosetting process is performed after the underfill resin layer 26is formed by the resin in the gap between the first semiconductor chip10 and the second semiconductor chip 30 as described above.

In the above thermosetting process, a reactant gas is emitted from thefillet of the underfill resin layer 26.

In the method for manufacturing the semiconductor device according tothe present embodiment, the above-described dam 25 prevents theprotrusion of the underfill resin layer 26 from the outer edge of thesecond semiconductor chip 30 to the side of the electronic circuitsection.

A distance of 200 μm or more can be secured between the fillet of theunderfill resin layer 26 and the electronic circuit section such as thesolid-state imaging device, the pad electrode and the like.

Therefore, the contamination of the electronic circuit section by thereactant gas emitted at a time of resin curing reaction from the filletof the underfill resin layer 26 can be prevented.

Thus, in the method for manufacturing the semiconductor device accordingto the present embodiment, the second semiconductor chip and theelectronic circuit section such as the pad electrode, the solid-stateimaging device or the like can be brought into proximity to each other,and thus the semiconductor device can be miniaturized.

Second Embodiment Constitution of Semiconductor Device

FIG. 7A is a plan view of a semiconductor device according to a presentembodiment. FIG. 7B and FIG. 7C are schematic sectional views takenalong lines X-X′ and Y-Y′, respectively, of FIG. 7A.

The fillet of an underfill resin layer 26 is not formed in a region ofthe periphery of a laminated second semiconductor chip in which region adam 25 prevents the protrusion of the underfill resin layer 26 from theouter edge of the second semiconductor chip 30 to the side of anelectronic circuit section.

The present embodiment has a layout such that the electronic circuitsection such as a pad electrode, a solid-state imaging section and thelike and the second semiconductor chip are adjacent to each other in theregion in which the dam 25 is formed. Being adjacent in this caseindicates that a distance between the electronic circuit section and thesecond semiconductor chip is zero or in the vicinity of zero.

Except for the above, the second embodiment has a similar constitutionto that of the first embodiment.

While a fillet is formed in a region in which the above-described dam 25is not formed, a dam is formed on all sides facing the electroniccircuit section. Thus, a sufficient distance of 200 μm or more can besecured as a distance between the fillet and the electronic circuitsection even in a part where the fillet and the electronic circuitsection are closest to each other.

Therefore, the contamination of the electronic circuit section by areactant gas emitted at a time of resin curing reaction from the filletof the underfill resin layer 26 can be prevented.

Thus, the second semiconductor chip and the electronic circuit sectionsuch as the pad electrode, the solid-state imaging device or the likecan be brought into proximity to each other, and thus the semiconductordevice can be miniaturized.

Third Embodiment Constitution of Semiconductor Device

FIG. 8A is a plan view of a semiconductor device according to a presentembodiment. FIG. 8B and FIG. 8C are schematic sectional views takenalong lines X-X′ and Y-Y′, respectively, of FIG. 8A.

A dam is formed in a shape along the outer edge of a secondsemiconductor chip. Specifically, in the present embodiment, arecess-shaped part 27 is formed in a ring-shaped bump 23 on the side ofa first semiconductor chip 10 which bump 23 forms a dam in a part inwhich a solid-state imaging section 11 is laid out close to the regionof the second semiconductor chip 30.

When an electronic circuit section such as a pad electrode 12, thesolid-state imaging section 11 and the like is present in the vicinityof the second semiconductor chip 30, and the length of the electroniccircuit section is shorter than the length of the side wall of thesecond semiconductor chip 30, it suffices to form a dam only in a partclose to the electronic circuit section.

Except for the above, the third embodiment has a similar constitution tothat of the first embodiment.

In the semiconductor device according to the present embodiment, anunderfill resin layer 26 has a fillet 26 a at a peripheral part of thesecond semiconductor chip 30 on which peripheral part the dam 25 is notformed.

However, the above-described dam 25 prevents the protrusion of theunderfill resin layer 26 from the outer edge of the second semiconductorchip 30 to the side of the electronic circuit section.

In the present embodiment, a sufficient distance of 200 μm or more canbe secured as a distance between the fillet of the underfill resin layer26 and the electronic circuit section such as the solid-state imagingdevice, the pad electrode and the like.

Therefore, the contamination of the electronic circuit section by areactant gas emitted at a time of resin curing reaction from the filletof the underfill resin layer 26 can be prevented.

Thus, the second semiconductor chip and the electronic circuit sectionsuch as the pad electrode, the solid-state imaging device or the likecan be brought into proximity to each other, and thus the semiconductordevice can be miniaturized.

As described above, the foregoing effects can be obtained even when thedam formation region is only in the vicinity of the electronic circuitsection.

Fourth Embodiment Method for Manufacturing Semiconductor Device

FIG. 9A and FIG. 9B are sectional views showing a process ofmanufacturing a semiconductor device according to a present embodiment,and are schematic sectional views corresponding to the lines X-X′ andY-Y′ in the semiconductor device shown in FIGS. 1A to 1C.

When an underfill resin layer is formed, a film-shaped underfill resinlayer 26 f may be formed on a second semiconductor chip 30, and thefilling of a resin serving as the underfill resin layer may be performedat the same time as the bump connection of a first semiconductor chip10.

Alternatively, a film-shaped underfill resin layer 26 f may be formed onthe first semiconductor chip 10, and the filling of a resin serving asthe underfill resin layer may be performed at the same time as the bumpconnection of the second semiconductor chip 30.

As shown in FIG. 9A and FIG. 9B, the film-shaped underfill resin layer26 f is subjected to pressure to fill the gap between the firstsemiconductor chip 10 and the second semiconductor chip 30, and asurplus is discharged to the outside of the gap. It is thereforeimportant to provide, in advance, a part serving as a resin outlet portfrom which the surplus can be discharged.

As described above, in the present embodiment, an electronic circuitsection is provided in each of parts adjacent to two opposed sides ofthe second semiconductor chip. The regions of two sides other than theabove sides are a resin outlet port.

Except for the above, the fourth embodiment has a similar constitutionto that of the first embodiment.

In the method for manufacturing the semiconductor device according tothe present embodiment, the above-described dam 25 prevents theprotrusion of the underfill resin layer 26 from the outer edge of thesecond semiconductor chip 30 to the side of the electronic circuitsection.

A distance of 200 μm or more can be secured between the fillet of theunderfill resin layer 26 and the electronic circuit section such as asolid-state imaging device, a pad electrode and the like.

Therefore, the contamination of the electronic circuit section by areactant gas emitted at a time of resin curing reaction from the filletof the underfill resin layer 26 can be prevented.

Thus, in the method for manufacturing the semiconductor device accordingto the present embodiment, the second semiconductor chip and theelectronic circuit section such as the pad electrode, the solid-stateimaging section or the like can be brought into proximity to each other,and thus the semiconductor device can be miniaturized.

Fifth Embodiment Constitution of Semiconductor Device

FIG. 10A is a plan view of a semiconductor device according to a presentembodiment. FIG. 10B and FIG. 10C are schematic sectional views takenalong lines X-X′ and Y-Y′, respectively, of FIG. 10A.

A dam for preventing the protrusion of an underfill resin layer 26 fromthe outer edge of a second semiconductor chip 30 to the side of anelectronic circuit section may be a resin material. A concrete exampleof the resin material is a photosensitive curing resin or athermosetting resin such as an epoxy resin, an acrylic resin or thelike.

Specifically, in the present embodiment, a resin layer 23 r is formed inplace of the under bump film 22 and the bump 23 on the side of a firstsemiconductor chip 10.

A resin layer 35 r is formed in place of the under bump film 34 and thebumps 35 on the side of the second semiconductor chip 30.

Further, a dam 25 r made of resin is formed with the above-describedresin layer 23 r and the resin layer 35 r adhering to each other on aperipheral part of the second semiconductor chip 30 on the side of theelectronic circuit section.

Except for the above, the fifth embodiment has a similar constitution tothat of the first embodiment.

In the semiconductor device according to the present embodiment, theunderfill resin layer 26 has a fillet 26 a at a peripheral part of thesecond semiconductor chip 30 on which peripheral part the dam 25 r isnot formed.

However, the above-described dam 25 r prevents the protrusion of theunderfill resin layer 26 from the outer edge of the second semiconductorchip 30 to the side of the electronic circuit section.

In the present embodiment, a sufficient distance of 200 μm or more canbe secured as a distance between the fillet of the underfill resin layer26 and the electronic circuit section such as a solid-state imagingdevice, a pad electrode and the like.

Therefore, the contamination of the electronic circuit section by areactant gas emitted at a time of resin curing reaction from the filletof the underfill resin layer 26 can be prevented.

Thus, the second semiconductor chip and the electronic circuit sectionsuch as the pad electrode, the solid-state imaging section or the likecan be brought into proximity to each other, and thus the semiconductordevice can be miniaturized.

[Method for Manufacturing Semiconductor Device]

FIG. 11A and FIG. 11B are sectional views showing a process ofmanufacturing a semiconductor device according to a present embodiment,and are schematic sectional views corresponding to the lines X-X′ andY-Y′ in the semiconductor device shown in FIGS. 10A to 10C.

In the present embodiment, a resin layer 23 r is pattern-formed in placeof the under bump film 22 and the bump 23 on the side of a firstsemiconductor chip 10.

In addition, a resin layer 35 r is pattern-formed in place of the underbump film 34 and the bumps 35 on the side of a second semiconductor chip30.

A method for pattern-forming the resin can be carried out by forming aresin material into a film by film lamination, spin coating or the likeand performing a photolithography process or the like.

A photosensitive curing resin or a thermosetting resin such as an epoxyresin or an acrylic resin, for example, can be used as the resin layer23 r and the resin layer 35 r.

Next, a dam 25 r made of resin is formed with the resin layer 23 r andthe resin layer 35 r adhering to each other on a peripheral part of thesecond semiconductor chip 30 on the side of the electronic circuitsection.

Heating at the time of bump connection or separate curing is performedfor adhesion between the resin layer 23 r and the first semiconductorchip 10, between the resin layer 35 r and the second semiconductor chip30, and between the resin layer 23 r and the resin layer 35 r.

Except for the above, the fifth embodiment has a similar constitution tothat of the first embodiment.

In the method for manufacturing the semiconductor device according tothe present embodiment, the above-described dam 25 r prevents theprotrusion of the underfill resin layer 26 from the outer edge of thesecond semiconductor chip 30 to the side of the electronic circuitsection.

A distance of 200 μm or more can be secured between the fillet of theunderfill resin layer 26 and the electronic circuit section such as asolid-state imaging section, a pad electrode and the like.

Therefore, the contamination of the electronic circuit section by areactant gas emitted at a time of resin curing reaction from the filletof the underfill resin layer 26 can be prevented.

Thus, in the method for manufacturing the semiconductor device accordingto the present embodiment, the second semiconductor chip and theelectronic circuit section such as the pad electrode, the solid-stateimaging section or the like can be brought into proximity to each other,and thus the semiconductor device can be miniaturized.

Sixth Embodiment Application to Electronic Device

FIG. 12 is a schematic block diagram of an electronic device as anelectronic device according to a present embodiment. The electronicdevice according to the present embodiment is an example of a videoelectronic device capable of photographing a still image orphotographing a moving image.

The electronic device according to the present embodiment has an imagesensor (semiconductor device having a solid-state imaging elementsection) 50, an optical system 51, a signal processing circuit 53, andthe like.

In the present embodiment, the semiconductor device having thesolid-state imaging element section according to each of the foregoingembodiments is incorporated as the above-described image sensor 50.

The optical system 51 forms an image of image light (incident light)from a subject onto the image pickup surface of the image sensor 50.Thus, a corresponding signal charge is accumulated within the imagesensor 50 in a certain period. The accumulated signal charge isextracted as an output signal Vout.

A shutter device controls a period of irradiation of the image sensor 50with light and a period of shielding the image sensor 50 from light.

The image processing section supplies a driving signal for controllingthe transfer operation of the image sensor 50 and the shutter operationof the shutter device. The signal transfer of the image sensor 50 isperformed according to the driving signal (timing signal) supplied fromthe image processing section. The signal processing circuit 53 subjectsthe output signal Vout of the image sensor 50 to various signalprocessing, and then outputs the result as a video signal. The videosignal resulting from the signal processing is stored on a storagemedium such as a memory or the like, or output to a monitor.

In addition, the present invention is not limited to application tosolid-state imaging element sections for sensing a distribution ofamounts of incident visible light and picking up the distribution as animage, the solid-state imaging element sections being provided insemiconductor devices.

The present invention is applicable to solid-state imaging sections forpicking up a distribution of amounts of incidence of infrared rays,X-rays, or particles or the like as an image and, in a broad sense,solid-state imaging sections in general such as fingerprint detectingsensors and the like for sensing a distribution of another physicalquantity such as pressure, capacitance or the like, and picking up thedistribution as an image.

In addition, the present invention is applicable to for example digitalstill electronic devices, video electronic devices, and electronicdevices having an imaging function such as portable telephones.

The image sensor 50 described above can be used as a semiconductordevice having a solid-state imaging element section, which is anelectronic device module or the like for video electronic devices anddigital still electronic devices as well as mobile devices such asportable telephones.

The present invention is not limited to the above description.

For example, while a pad electrode and a solid-state imaging sectionhave been described as an electronic circuit section, an embodiment ofthe present invention is applicable to other electronic circuitsections.

The embodiment of the present invention is applicable to various sensorssuch as a CMOS (Complementary Metal Oxide Semiconductor) image sensorand a CCD (Charge Coupled Device) image sensor as the solid-stateimaging section.

In addition, various changes can be made without departing from thespirit of the present invention.

The present application contains subject matter related to thatdisclosed in Japanese Priority Patent Application JP 2010-111910 filedin the Japan Patent Office on May 14, 2010, the entire content of whichis hereby incorporated by reference.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factor in so far as they arewithin the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. A semiconductor device comprising: a firstsemiconductor chip having an electronic circuit section formed at leaston one surface of the first semiconductor chip, and having a firstconnecting section formed on a same surface as the surface of formationof said electronic circuit section; a second semiconductor chip having asecond connecting section formed on one surface of the secondsemiconductor chip, the second semiconductor chip being mounted on saidfirst semiconductor chip with said first connecting section and saidsecond connecting section connected to each other by a bump; a damformed so as to fill a gap between said first semiconductor chip andsaid second semiconductor chip on at least a part of an outer edge ofsaid second semiconductor chip, the part of the outer edge of saidsecond semiconductor chip being on a side of a region of formation ofsaid electronic circuit section; and an underfill resin layer providedin the gap between said first semiconductor chip and said secondsemiconductor chip such that a protrusion of the underfill resin layerfrom the outer edge of said second semiconductor chip to a side of saidelectronic circuit section is prevented by said dam, wherein saidunderfill resin layer includes a protrusion from at least a part of anouter edge of said second semiconductor chip where said dam is notformed.
 2. The semiconductor device according to claim 1, wherein saiddam is formed by a same layer as a conductive layer forming said bump.3. The semiconductor device according to claim 1, wherein said dam isformed by a resin.
 4. The semiconductor device according to claim 1,wherein said electronic circuit section is a pad electrode.
 5. Thesemiconductor device according to claim 1, wherein said electroniccircuit section is a solid-state imaging section.
 6. The semiconductordevice according to claim 1, wherein said electronic circuit section andsaid second semiconductor chip are formed so as to be adjacent to eachother.
 7. The semiconductor device according to claim 1, wherein saiddam is formed in a shape along the outer edge of said secondsemiconductor chip.
 8. A method for manufacturing a semiconductordevice, said method comprising the steps of: forming an electroniccircuit section at least on one surface of a first semiconductor chip,and forming a first connecting section on a same surface as the surfaceof formation of said electronic circuit section; forming a secondconnecting section on one surface of a second semiconductor chip;mounting said second semiconductor chip on said first semiconductor chipwith said first connecting section and said connecting section connectedto each other by a bump; forming a dam for filling a gap between saidfirst semiconductor chip and said second semiconductor chip on at leastpart of an outer edge of said second semiconductor chip, the part of theouter edge of said second semiconductor chip being on a side of a regionof formation of said electronic circuit section; and forming anunderfill resin layer so as to fill the underfill resin layer into thegap between said first semiconductor chip and said second semiconductorchip such that a protrusion of the underfill resin layer from the outeredge of said second semiconductor chip to a side of said electroniccircuit section being prevented by said dam, wherein said underfillresin layer includes a protrusion from at least a part of an outer edgeof said second semiconductor chip where said dam is not formed.
 9. Themethod for manufacturing the semiconductor device according to claim 8,wherein in the step of forming said dam, said dam is formed by a samelayer as a conductive layer forming said bump.
 10. The method formanufacturing the semiconductor device according to claim 8, wherein inthe step of forming said dam, said dam is formed by a resin.
 11. Themethod for manufacturing the semiconductor device according to claim 8,wherein in the step of forming the electronic circuit section at leaston one surface of the first semiconductor chip, a pad electrode isformed as said electronic circuit section.
 12. The method formanufacturing the semiconductor device according to claim 8, wherein inthe step of forming the electronic circuit section at least on onesurface of the first semiconductor chip, a solid-state imaging sectionis formed as said electronic circuit section.
 13. The method formanufacturing the semiconductor device according to claim 8, wherein inthe step of mounting said second semiconductor chip, said secondsemiconductor chip is mounted so as to be adjacent to said electroniccircuit section.
 14. The method for manufacturing the semiconductordevice according to claim 8, wherein in the step of forming said dam,said dam is formed in a shape along the outer edge of said semiconductorchip.
 15. The method for manufacturing the semiconductor deviceaccording to claim 8, wherein in the step of forming said underfillresin layer, said underfill resin layer is formed by laminating a resinfilm to a side of the surface of formation of the second connectingsection of said second semiconductor chip and mounting said secondsemiconductor chip onto said first semiconductor chip.
 16. An electronicdevice comprising: a solid-state imaging device; an optical system forguiding incident light to an imaging section of said solid-state imagingdevice; and a signal processing circuit for processing an output signalof said solid-state imaging device; wherein said solid-state imagingdevice includes: a first semiconductor chip having a solid-state imagingsection formed at least on one surface of the first semiconductor chip,and having a first connecting section formed on a same surface as thesurface of formation of said solid-state imaging section, a secondsemiconductor chip having a second connecting section formed on onesurface of the second semiconductor chip, the second semiconductor chipbeing mounted on said first semiconductor chip with said firstconnecting section and said second connecting section connected to eachother by a bump, a dam formed so as to fill a gap between said firstsemiconductor chip and said second semiconductor chip on at least a partof an outer edge of said second semiconductor chip being on a side of aregion of formation of said solid-state imaging section, and anunderfill resin layer provided in the gap between said firstsemiconductor chip and said second semiconductor chip such that aprotrusion of the underfill resin layer from the outer edge of saidsecond semiconductor chip to a side of said solid-state imaging sectionis prevented by said dam, wherein said underfill resin layer includes aprotrusion from at least a part of an outer edge of said secondsemiconductor chip where said dam is not formed.
 17. The electronicdevice according to claim 16, wherein said dam is formed by a same layeras a conductive layer forming said bump.
 18. The electronic deviceaccording to claim 16, wherein said dam is formed by a resin.
 19. Theelectronic device according to claim 16, wherein said solid-stateimaging section and said second semiconductor chip are formed so as tobe adjacent to each other.
 20. The electronic device according to claim16, wherein said dam is formed in a shape along the outer edge of saidsecond semiconductor chip.